CANOGA PERKINS 9161 Network Interface Device - Manual (Page 35)

9161 Network Interface Device 3-21
A
C
E
B
D
1
2
3 4
5 6
A small test network
A
C
E
B
D
1
2
3 4
5 6
Spanning Tree from source (C)
Figure 7. Typical Spanning Tree Application
In a service provider environment, you can include VLANS from different customers. The tagging
and double tagging features, when enabled, keep the ID tag on a packet as it exits a port; or when
disabled, strip the ID tag as it exits a port. The customer's tag for a VLAN is assigned through the
VLAN; the double (service provider's) tag is derived from the PVID and assigned before the packet
exits the 9161. See Figure Error! Reference source not found. and follow these guidelines:
• Enable double tagging on the service provider port and disable it on the customer's port.
• The SP tag priority is derived from the port priority.
• If you set up Pbit translation, the translation occurs before the Pbit is copied to the SP tag.
Customer port 1 Customer port 1
Customer port x Customer port x
Service Provider port 1 Service Provider port 1
Service Provider port 2 Service Provider port 2
Packet
Packet
Packet
Service
Provider ID
Customer
VLAN ID
Customer
VLAN ID
Customer
VLAN ID 3
3
3
5
Figure 8. Double Tagging Example
When setting up ports in the various switch configuration options, set up and configure options in this
order:
1. Set up the physical layer, such as port speeds.
2. Set up STP parameters for the physical ports.
3. Set up the VLANS.
4. Set up the Multiple Spanning tree (MST) parameters.
5. When all aspects of the link are ready, connect cables and start the network services.